• Proceedings of the SAREK Conference
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• 2004.06a
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• pp.118-118
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• 2004

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.4
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• pp.325-336
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• 2000

During the last decade, an increasing interest in Underfloor Air-Conditioning(UFAC) systems has emerged. The purpose of this paper is to evaluate comprehensively the indoor environmental performance of office buildings with UFAC system in order to develope the design prototype of this system. In this paper, the physical measurements and the interviewing survey of occupant's sensation responses to the environment were carried out. Measurements and survey were made of the thermal environmental factors such as air temperature, relative humidity, air velocity, globe temperature, and the other several environmental factors such as the sound level and the illuminance of working plane, etc. And, the air quality was evaluated by measuring the concentration of suspended particles, carbon monoxide, and carbon dioxide in the room. Furthermore, the paper appraises the various indoor environmental factors of the room by using post-occupancy evaluation(POE) method in office building with UFAC system, and thus, it suggests the basic data for assessing the indoor comfort based on field measurements and survey.

• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.49-49
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• 2004

• Journal of Power System Engineering
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• v.10 no.4
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• pp.43-49
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• 2006

Nowadays, the thermal environments of classrooms are usually adjusted by the ceiling type air-conditioning system with a temperature sensor installed on inlet of an air-conditioner. However, it is not clear that the conventional temperature sensor position is proper to satisfy both thermal comport and energy saving in summer especially. Therefore, this study is aimed at finding out the best position of the temperature sensor on the purpose of the comfort thermal environment and energy saving. The different 5 positions for the temperature sensor are supposed in this paper to analyze thermal environment by CFD. From the analysis through the CFD simulations, the best position of the temperature sensor satisfying for both comfort thermal environment and energy saving is obtained.

• Special Issue of the Society of Naval Architects of Korea
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• 2017.10a
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• pp.67-72
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• 2017

This paper presents on the evaluation of thermal comfort in office on offshore. In living quarter of offshore, strict air conditioning performance is required to office on offshore and displacement ventilation is applied to office space which rooms are required to confirm the thermal environment. The computational fluid dynamics (CFD) is performed to calculate the temperature, air velocity in office and thermal comfort such as PPM & PPD is evaluated by the CFD result.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.12
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• pp.857-864
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• 2007

In the current residential building, hot water supply system consumes the second largest energy in order to make the thermal comport condition of residential space. The more residential environment improves the more the demand for hot water and water consumption is increasing gradually. So this study examines the possibility of applying the recirculation for individual hot water supply system compared with the existing method for waiting time for hot water, wasted water and energy consumption. The results are as follows. (1) In case of recirculation system method the waiting time for hot water can be reduced up to $69\sim85%$ in spring and fall period and so dose up to $77\sim85%$ in winter period. (2) The total wasted water has a little change compared with the existing method which can make the total wasted water reduced about $77\sim86%$. (3) The efficiency of hot water supply system can be improved, if the method which blocks the inflow of cold water is applied, when return pump is operated to recirculate hot water in recirculation system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.12
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• pp.1204-1211
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• 2004

It is difficult to apply a conventional selection guide for diffusers when the diffuser is installed in a perimeter zone, because the air diffusion performance index (ADPI) vs. throw/length (T/L) ratio curve listed in conventional guide does not consider the perimetric heating load through the walls. The objective of this study is to evaluate the effect of the perimetric heating load on the ADPI and propose a selection guide for a proper line diffuser when perimetric heating load exists. The velocity and temperature distributions and the ADPI values are obtained numerically with various heat load ratios and air flow rates. The velocity and temperature distributions and the ADPI values are analyzed by CFD in case of various heat load ratios and air flow rates. Also, ADPI was calculated by those results. The ADPI values by numerical results are compared with an existing experimental data to verify the method for the evaluation of ADPI proposed in a present study. In case of a line diffuser installed at the high side wall, the ADPI decreases according to the increases of the flow rate on every heat load ratio of the present study except 0.75. The ADPI vs. T/L ratio curves have been proposed for the heat load ratios of 0.25, 0.5, 0.75 to guarantee the comport thermal environment when diffusers are installed in perimeter zone.